The invention relates to a mechanical chock with cams for climbing and mountaineering, and comprising:                at least one pair of anchoring cams mounted in rotation and in opposition on a common support spindle, each cam comprising a bearing surface having a predetermined profile,        an attachment means securedly affixed to a central body of the spindle, which is equipped with a first half-spindle for receiving the first cam and a second half-spindle for receiving the second cam,        and means for operating the cams between a separated blocking position and a retracted releasing position.        